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#ifndef LOC2STAP_H
#define LOC2STAP_H 1
#include "staptree.h"
#include <elfutils/libdw.h>
enum location_type
{
loc_address, loc_register, loc_noncontiguous, loc_unavailable,
loc_value, loc_constant, loc_implicit_pointer,
loc_decl, loc_fragment, loc_final
};
struct location
{
location_type type;
unsigned byte_size;
// loc_address, loc_value, loc_fragment, loc_final
expression *program;
// loc_register
unsigned int regno;
// loc_noncontiguous
location *pieces;
location *piece_next;
// loc_constant
const void *constant_block;
// loc_implicit_pointer
location *target;
// loc_register, loc_implicit_pointer
Dwarf_Word offset;
location(location_type t = loc_unavailable)
: type(t), byte_size(0), program(0), regno(0), pieces(0),
piece_next(0), constant_block(0), target(0), offset(0)
{ }
};
struct dwflpp;
class location_context
{
public:
const target_symbol *e_orig; // unmodified original
target_symbol *e; // deep-copied + rewritten, for use within synthetic _dwarf_tvar* function body
// These three form the argument list to the function, in sequence.
// They will be referenced by the expression(s) computing the location.
vardecl *pointer;
std::vector<vardecl *> indicies;
vardecl *value;
Dwarf_Attribute *attr;
Dwarf_Addr dwbias;
Dwarf_Addr pc;
Dwarf_Attribute *fb_attr;
const Dwarf_Op *cfa_ops;
dwflpp *dw;
// Temporaries required while computing EVALS and LOCATIONS.
symbol *frame_base;
std::vector<vardecl *> locals;
std::vector<statement *> evals;
std::vector<vardecl *> globals;
std::map<Dwarf_Addr, block *> entry_probes;
Dwarf_Die *function;
Dwarf_Die *parameter_ref;
std::vector<location_context> call_site_values;
int param_ref_depth;
// A set of locations which have been requested to be evaluated.
// The last one can be considered "current", and thus the result
// is locations.back()->program.
// ??? This is the old loc->next list. Should we just have a
// single pointer here instead?
std::vector<location *> locations; // ??? old loc->next list
// The dwarf is within a user (vs kernel) context.
bool userspace_p;
location *new_location(location_type);
location *new_location(const location &old);
symbol *new_symref(vardecl *var);
symbol *new_local(const char *namebase);
expression *new_target_reg(unsigned regno);
expression *new_plus_const(expression *, int64_t);
expression *save_expression(expression *);
symbol *frame_location();
void adapt_pointer_to_bpf(int size, int offset, bool is_signed);
expression *handle_GNU_entry_value(Dwarf_Op expr);
expression *handle_GNU_parameter_ref(Dwarf_Op expr);
location *translate(const Dwarf_Op *expr, size_t len, size_t start,
location *input, bool may_use_fb, bool computing_value);
location *location_from_address (const Dwarf_Op *expr, size_t len,
location *input);
location *translate_offset (const Dwarf_Op *expr, size_t len, size_t i,
location *input, Dwarf_Word offset);
location *location_relative (const Dwarf_Op *expr, size_t len,
location *input);
location *translate_array_1(Dwarf_Die *anydie, Dwarf_Word stride,
location *loc, expression *index);
public:
location_context(target_symbol *, expression * = NULL);
expression *translate_address(Dwarf_Addr a);
location *translate_constant(Dwarf_Attribute *a);
location *translate_location(const Dwarf_Op *locexpr,
size_t locexprlen, location *input);
location *translate_argument (expression *value);
location *translate_argument (vardecl *var);
location *translate_array(Dwarf_Die *typedie, location *, expression *);
location *translate_array_pointer(Dwarf_Die *typedie, location *input,
expression *index);
location *translate_array_pointer (Dwarf_Die *, location *input,
vardecl *index);
location *discontiguify(location *loc, Dwarf_Word total_bytes,
Dwarf_Word max_piece_bytes);
};
#endif
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